This is from @stevenmarx on Printables, but I wanted a profile on MakerWorld because it's fantastic and easy to print. I'm starting off with basic models and will be adding more in as I go.

Please visit the author's page on Printables: https://www.printables.com/model/1035644-wilma-tuftelbausteine-open-source-prototyping-kit and their other amazing content from their website (in German): https://erfinderbaukasten.wilmaonline.net/